No matter how many tough securities laws are passed, or how many “messages” are sent by zealous prosecutors or how many pious pronouncements are made by regulators, a Madoff-type scandal will inevitably happen again. That’s the warning of a veteran of the securities industry.

“Wall Street is a cesspool, and nothing has really changed since Madoff,” says Bill Singer, a longtime securities attorney with Herskovits PLLC.

Singer, who has some 30 years in the securities industry, says regulators and prosecutors are frequently unrealistic about human nature.

“Just after the Madoff sentencing happened, I was asked by a television journalist if this didn’t send a message, if this wouldn’t discourage more fraud from happening,” Singer said. He told the journalist it wouldn’t.

“There are people on Wall Street, even as Madoff was sentenced, who were saying that they could have pulled off what Madoff did and not get caught,” according to Singer.

Singer’s comments come in the wake of a consultant’s report that argued the threat of massive fraud remains.

The Tabb Group, a New York-based market consulting and advisory firm, cites in a recent report two reasons the spirit of Madoff continues in the securities business: In 2011, the FBI launched about 1,000 inquiries into possible fraud schemes, and the Securities and Exchange Commission has been ramping up its probes of companies and institutions suspected of fraud.

“These two tidbits of information would suggest that even in the aftermath of the largest Ponzi scheme ever seen, investors and institutions must remain aware that fraud is still prevalent,” according to Joel Cohen of Kinetic Partners, the author of the report.

Cohen’s firm is a professional advisory services firm that investigates for fraud through its forensic accounting services.

Most of Singer’s contemporaries aren’t nearly as outspoken about the securities industry. Nevertheless, most of them privately concede that his prediction is essentially correct.

Opportunities to cheat are increasing because the speed and sophistication of markets are themselves increasing, explains Alexander Tabb, a partner with the Tabb Group.

“Markets are moving at nanosecond speeds. Trading now is going on in multiasset categories, and there are now more rules. And that means it is more difficult to enforce these rules,” Tabb says.

Tabb adds that, since the passage of the Dodd-Frank Act, there are now many more rules to enforce.

And the further one moves from a scandal, industry observers say, the more likely it is to recur, as memories dim.

“People have short-term memories,” Cohen says. “Right after the Madoff scandals broke, they focused on implementing a robust infrastructure with internal controls and compliance. Now I see some of them going back to their old ways.”

The lesson for investors and officials of financial firms, professionals say, is don’t depend on others. Do one’s own due diligence.

“I’d like to say never again,” Cohen says of the Madoff scam. “But the SEC is often overburdened and has a lot on its plate.”